Functional Mock-up Interface (FMI) Import in Wolfram SystemModeler
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FMI import allows you to use subsystems from other tools in your modeling and simulation workflow with SystemModeler and the Wolfram Language. Explore imported models within SystemModeler by changing parameters and observing the outcomes. Post-process and visualize simulation data from imported models with the Wolfram Language. With automated reports and cloud features, sharing the results and the insight gained from the simulations is a straightforward task.
Let’s take a look at what importing and using a Functional Mock-up Unit can look like. Drag and drop the unit into SystemModeler and follow the dialogs to import the model into the class browser. This is what it looks like when we import a model exported from Simulink using the FMI Toolbox from Modelon:
The unit is now available inside SystemModeler, and we can connect it to other components. In this case it’s a model of a cruise control. We connect it to a model of a car to see how well it can control the speed of the car.
Next we can perform a parameter sweep in the Wolfram Language to analyze the speed deviations when trying the controller at different speeds. These plots show speed deviations for a car going downhill:
Another way to view the data is to create a DensityPlot showing the relative speed deviation from the reference speed.
The plot shows that the cruise control performs best on flat or slightly uphill grades. This region is colored green, the color for less than 1% speed deviation. If you drive at 40 km/h on a 2-degree incline, you would be in this region. The worst performance can be found in the red region, with more than 5% speed deviation. If you drive at 30 km/h on a 3-degree decline, you would be in this region.
FMI import and export are included in SystemModeler and do not require any extra purchases or special add-ons. With FMI, simulations from modeling and simulation experts can be deployed to a large number of consumers who can use the models in their analysis and design tasks. Look here for an example of how to export a model from SystemModeler and use it in another tool.